Austenite Grain Growth Behavior of 30BF Steel Before Rough Rolling

Yong‑feng Chen,Jian‑bo Xie,Yan‑xin Wu,Jian‑xun Fu 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.4

To investigate the eff ect of heat treatment on the grain size of austenite in 30BF steel, the comparisons of the morphologiesand sizes of austenite grains between heating samples were made with a high-temperature electric resistance furnace, andthe austenite growth models were built with method of mathematics. The results show that most grains in original specimenwith the sizes below 70 μm uniformly distributed. At a heating rate ( v ) of 10 °C/s, the grain size ( d ) value under a certain time( t ) increased by 60–100 μm with raising temperature ( T ) from 850 to 1100 °C, whereas the d value under a certain T merelyincreased by 70–120 μm with raising time to 60 min. Under v = 0.1 °C/s, T = 850 °C, and t = 0 s, the occupied ratio of grainswith sizes of 40–50 μm was 0.165, whereas at 900 °C, the occupied ratio was 0.125. The evolutions of ln (d5.8− d5.80 ) with1/ T were in negative linear correlations, whereas the ln (d5.8− d5.80 ) with ln t were in positive linear correlations. To sum up,the grain growth behavior of steel was elucidated.

대학생들의 여가경험과 몰입경험이 인지된 행복감에 미치는 영향

김보겸(Kim, Bo-Kyoum),신용업(Shin, Yong-Eup),장성호(Jang, Sung-Ho),이태현(Lee, Tae-Hyun) 한국체육과학회 2013 한국체육과학회지 Vol.22 No.3

This study examined the effect of University students’ leisure and flow experience on happiness. The research was made with 258 students from University which are located in Suwon, Ansan, and Yongin province. Survey data were collected through survey questionnaires and were analyzed with SPSS 18.0, and An10S 18.0 programs. The results of this study based on above methods and procedures were as followings. First, students’ leisure experience had significant effect on cognitive happiness. Second, students’ leisure flow experience had significant effect on cognitive happiness. Shin, Yong-Eup

T 세포활성항원 CTLA-4의 기능에 관한 연구 : T 세포에서 표적세포 살해능과 CTLA-4 발현과의 연관성 Target Cytotoxicity of T Cell Correlates with CTLA-4 Production

노만택,조양자,김용식,최용,조보현,최장원,정용훈 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.4

CTLA-4, a T cell activation antigen and a homologue of CD28, was originally identified as a gene by a series of reverse genetic approaches. While CD28 molecule has been characterized well as a stimulator of T-cell function via enhanced lymphokines production and stablilization of those mRNA, most of the functions of CTLA-4 remain unknown. It has been widely accepted that CTLA-4 functions as an immune suppressor which is down-regualting the function of CD28. We previously showed that 34 KD form of this antigen mainly expressed CD8+ subset, a cytotoxic or suppressor, of activated peripheral blood lymphocyte. Based on our previous finding this study was conducted to further characterize immunological function of CTLA-4 especially in terms of involvement of this molecule in T-cell effector function mediating target cell cytotoxicity. 4 human T cell clones with different target cytotoxicities were employed in this study. NBL46 (CD4+) and NBL77 (CD8+) were cytotoxic and NBL32 (CD4+) and NBL58 (CD 8+) were non-cytotoxic to target LBF cell in target cell chromium release assay. And in Western blot assay 34 kD antigen was detected in NBL46 (CD4+) and NBL77 (CD8+) clones but not in NBL32 (CD4+) and NBL58 (CD8+) clones. It was summarized that expression of the CTLA-4 antigen was associated with cytotoxicity but not with subset phenotypes of T cells. In conclusion CD8+ T subset of PHA-stimulated PBL was major and only CTLA-4 producer and this molecule was induced during mid to late stage of T cell activation. The cytotoxicity of T cell clones to its target cell was directly correlated with its CTLA-4 production and vice versa. And it was highly suggested that primary function of CTLA-4 may involved in T cell effector function which mediates target cell killing.

우심방을 침범한 거대 비호지킨씨 림프종 1예

강상범,진승원,이은경,박용현,최용호,김용주,박준철,김재형,홍순조,최규보,권종범,원용순,박건,이은희 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.4

특성불안이 높은 성인과 낮은 성인에서 알코올이 정신운동성 수행과 주관적 평가에 미치는 영향

용화영,윤보현,윤진상 大韓神經精神醫學會 1996 신경정신의학 Vol.35 No.5

Objectives : The purpose of this study was to evaluate effects of alcohol on psychomotor performance and subjective assessments in normal adults with high and low trait anxiety. Methods : The subjects consisted of 11 men in each group were tested with two doses of alcohol(0.25g/㎏ and 0.75g/㎏). Blood alcohol concentration(BAC), psychomotor performance(critical flicker fusion threshold, CFFT ; choice reaction time, CRT) and subjective assessment were measured at pre-alcohol baseline and 20, 40, 80, and 160 minutes after intake of alcohol. Results : 1) There was no significant difference in BACs between two groups at any time points after intake of each dose of alcohol. 2) After intake of 0.25g/kg alcohol, high anxiety group, compared to low anxiety group, reported less anxious and more relaxed feelings. In psychomotor performance test, however, there was no significant difference between the two groups. 3) After intake of 0.75g/kg alcohol, CFFT was increased in high anxiety group while it was decreased in low anxiety group. In subjective assessment, only high anxiety group tended to show more positive response. Conclusion : These results imply that alcohol may be more beneficial in individuals with high trait anxiety than those with low trait anxiety in terms of objective performance and subjective feelings. Furthermore, these suggest that the alcohol benefits might contribute to drinking more alcohol and frequently in individuals with high trait-anxiety.

朝鮮時代 上流住宅 사랑채 樓마루의 外部空間的 特性에 關한 硏究

사공영보,김용기 한국정원학회 2002 한국전통조경학회지 Vol.20 No.4

This study examined the ralationships between the roo-maru(Raised Floor) platforms and their exterior spaces in the Korean gentry houses of Chosun Dynasty. Those 22 houses selected for the subjects of this stufy, retained their original forms intact, were known exactly when they were constructed, and had related data abundantly. Their original owner, their physical charateristics and their exterior-space features were analyzed. The exterior-space features were examined, focused on the view from the roo-maru, its directional relationship with the main building, the relationship with the yard and the outer space, its constituent elements, and its relationship of the garden and the outer sapce. 1. The floor heights of the roo-maru and its surrounding walls were set so as to secure the view of the outer space. 2. The yards were classified into two categories: when there was a fine prospect in the exterior space, no artificial garden was made in the yard; if not, there was built an artificial garden in the yard. 1) When it was vacant, the yard had 1-2 scholar trees, or 1-2 deressed stones or stone images in front of the roo-maru, giving a special meaning to the space. 2) When an artificial garden was built, it was generally composed of trees, some of the landscape items such as artificial hills, ponds, dressed stones, oddly shaped stones, stone images, terraced flower beds, or mounded flower beds. The trees planted in the garden were 23 evergreen species and 43 deciduous species, which means the deciduous were more favored than the evergreen as garden items. 3. According to the topographical features of the site, the front of the roo-maru was opened or closed by tree planting or pond digging.

의약품중 잔류유기용매 시험법 확립에 관한 연구

고용석,강찬순,최보경,김혜수,홍정희,최명신,김상현,장성재,김길수 식품의약품안전청 2001 식품의약품안전청 연보 Vol.5 No.-

Headspace-GC(딘5-GC)를 이용하여 ICH 잔류웅매 가이드라인 class 1, 2에 속하는 28종의 잔류유기웅매 분석방법을 연군한 결과 SPB-5, BB-WAX column을 동시 이용하여 각각을 확인, 정량할 수 있었다.또한 염의 참가효과, 평형시간,평형온도가 headspace분석에 미치는 영향을 검토한 결과 평형 시간 30분,평형온도 85℃,Na₂SO₄Ig을 첨가하여 시험할 때 최적 부넉조건을 나타내었다. 회수율은 1,1-achloroethene(68.3%)를 제외하고 90.9 ~ 114.5%로 패체적으로 양호하였다. 따로 HS-GCJECD, DB-524 column을 이용하여 9종의 잔류유기용매에 대하여 각각의 검랸선을 작성하고 검출한계를 구하였다. 실제 의약품 원료 10종및 제제 5종에 적용시킨 결과 모두 불검출되었으며 본 시험법은 의약품중의 잔류유기용매 분석에 적용할 수 있는 방법이라고 판단된다. The headspace-fC/FID(HS -GC/FID) method was performed for test method developnlent of residu;31 organic solvents in pfrarmaceuticals. Using SPB-S and BB-WAXcolumn, 28 kinds of solvents iri ICH residual sof)·ents guidetine class 1, 2 couBd be individuallt-identified and quantitated. The foIBowing residoal soIYents were not detected by the headspaceinjection condition : N,N-Cmethylacetamide, N,N-dimeth)rlformamide, ethyfeneglycol, formamide,2-methoryethanot, N-rnethylpyrrolidone, suBforane. The effects of the addition of salts,equilibration time, and equilibration temperature on headspace analt·sis were invesugated. Theoptimum conditions weiFe obtained with addtion of Ifa2s04 19 as a salt, simultaneously. thetime and temperature of equitibration were 30min and 8i'f, respectivety. The recovery havefound between 90.9 and 114.5% except 1,1-dichloroethene(fi8.3%). Using DB-624 column &HS-GC/:ECD method, 9 kinds of residual solvents could be individually identified andfuantitated. This HS-GC method can be applied to test the residua3 organic solvent in thepharmaceuticals.

이동객체의 궤적처리를 위한 트리기반 색인기법의 성능분석

심춘보,신용원 한국지리정보학회 2004 한국지리정보학회지 Vol.7 No.4

본 연구에서는 GIS 응용에서 이동객체의 궤적을 인덱싱하기 위해 기존에 제안되었던 TB(Trajectory-Bundle)-트리의 성능을 개선시킬 수 있는 연결테이블(LinkTable:L-Table) 기반의 확장된 TB-트리(L-Table TB-Tree:LTB-Tree)를 제안하고 아울러 제안하는 색인기법의 성능평가를 위해 다음과 같은 사항을 고려한다. 첫째, 기존의 R*-트리, IB-트리, 그리고 제안하는 LTB-트리를 성능평가 대상으로 선정한다. 둘째, 실험 데이타 집합으로는 랜덤 데이타 집합 및 실제 데이타 집합을 이용한다. 셋째, 시스템의 가용 메모리의 제약을 고려해 메모리 버퍼 크기에 따른 성능평가를 수행한다. 넷째, 다양한 데이타 분포도를 가지고 있는 실험 데이타를 이용하여 성능평가를 수행한다. 마지막으로 삽입성능 및 검색성능(궤적질의 및 영역질의)을 평가한다. 성능평가를 분석한 결과, 제안하는 색인기법이 기존의 색인기법들에 비해 삽입과 궤적질의의 검색 측면에서 더 우수함을 보인다. In this study, we propose Linktable based on extended TB-Tree (LTB-Tree) which can improve the performance of existing TB (Trajectory-Bundle) -tree proposed for indexing the trajectory of moving objects in GIS Applications. In addition, in order to evaluate proposed indexing scheme, we to ke into account as follows. At first, we select existing R^*-tree, TB-tree, and LTB-tree as the subject of performance evaluation. Secondly, we make use of random data set and real data set as experimental data. Thirdly, we evaluate the performance with respect to the variation of size of memory buffer by considering the restriction of available memory of a given system. Fourth, we test them by using the experimental data set with a variation of data distribution. Finally, we think over insertion and retrieval performance of trajectory query and range query as experimental measures. The experimental results show that the proposed indexing scheme, LTB-tree, gains better performance than traditional other schemes with respect to the insertion and retrieval of trajectory query.

사람 HPRT 유전자 발현벡터 제조와 생쥐 Sp2/0 myeloma 세포주에서의 발현

고창보,김용만,김영진,백상기 충남대학교 기초과학연구소 1997 忠南科學硏究誌 Vol.24 No.1

To construct expression vector for the human HPRT gene, pRSVneo plasmid conferring resistance to neomycin-kanamycin(Tn5) antibiotics and pHPT 31 containing human HPRT cDNA were used to subclone human HPRT cDNA. For construction of recombinant pRSVneo carrying human HPRT, pRSVneo-HPRT, the human HPRT cDNA fragment from pHPT31 plasmid was inserted into polyadenylation site (BamHI site) behind the neo gene fragment of pRSVneo plasmid. For the other expression vector, pRSV-HPRT, the neo gene and small portion of the untranslated 5′franking region were removed from the pRSVneo-HPRT. The HPRT gene of the two vectors were constructed in right orientation. Each recombinant vector was introduced into cultured HPRT-deficient mouse cell line, Sp2/0 by calcium mediated DNA transfection and the transfected cells were selected under HAT selection condition. The HPRT activity of the lysates from the selected cell was higher than that of the lysates from spleen cells of mouse. The HPRT activity of pRSVneo-HPRT vector was higher than that of pRSV-HPRT one. To find out whether the HPRT activity of the transfected cells selected under HAT medium was expressed by transfected vectors or by spontaneous mutations, it was cultured to reselect in G418 medium. It showed that the nature of the HPRT activity was resulted from the transfected vectors.

상악동을 침범하는 역위성 유두종의 증례보고

지용화,최보람,허경회,안창현,이삼선 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.2

The present study reports a case of inverted papilloma of the nasal cavity and infiltrating into the maxillary sinus. Inverted papilloma is an uncommon and locally aggressive benign tumor of the sinonasal region. The patient, 51-year-old male, presented with unilateral nasal obstruction and periodic swelling on the palate without pain. Enhanced CT scan revealed a heterogeneously enhancing solid mass in the nasal cavity and infiltrating into the right maxillary sinus, as well as an incidental, secondarily infected residual cyst m the periapical area of the right maxillary canine. The sinonasal mass was revealed as an inverted papilloma on histopathologic examination.